Projector for page printers



July 2, 1946. w. J. ZENNER 2,403,320

I PROJECTOR FOR PAGE PRINTERS Original Filed-- July 17, 1940 5Sheets-Sheet 2 FIG.2 w

ORNEY:

July 2, 1946. w. J. ZENNER 2,403,320 PROJECTOR FOR PAGE PRINTERSOriginal Filed July 17, 1940 SRSheets-Sheet 3||||||l||||||llIIIIIIIIIIIIIMIII-IIE wuuuuu uuuuuuuuuuuuuutlmw INVENTOR.WALTER J. ZENNER BY J I I ZTTORNW 4 FIG.3

July 2, 1946. w. J. ZENN ER PROJECTORlF-OR PAGE PRINTERS Original FiledJuly 17. 1940 5 Sheets-Sheet 4 FIG. 4 6

. 8| n7 '8' 82 I94 I I I I97 INVENTOR. WALTER J. ZENNER J65 W ATTORNEY.

July 2, 1946. w; J.. ZENNER 2,403,320

PROJECTOR FOR PAGE PRINTERS Original Filed July 17, 1940 5 Sheets-Shem;5

FIG. 9

//VV[/V70A WALTER J. ZENNER Patented July 2, 1946 UNITED STATES PATENTOFFICE PROJECTOR FOR PAGE PRINTERS tion of Delaware Original applicationJuly 17, 1940, Serial No. I

Divided and this application September 18, 1941, Serial No. 411,375

4 Claims. 1 The present invention pertains to printing telegraphapparatus and more particularly toypa'g'e printers for use in projectionsystems.

This application is a division of application Serial No. 346,004, filedJuly 17, 1940.

The primary object of the invention is to provide a page printer whichlends itself readily and etliciently to a projection system fordisplaying on a screen telegraphically received message .matter.

Another object of the invention is to provide a printer-projector inwhich the parts of the receiving printer are arranged and constructed tofacilitate the projection and display of printed matter resulting fromoperation of a printing telegraph receiver. V

According to the present invention a projectio system has been providedwhich embodies apage printer, of the .type shown in U. S. Patent No.1,904,164, designed to give upon a screen a running account of receivedmessage matter, through the instrumentality of an optical systemcomprising an arrangement of inclined mirrors so that the printer andlamp housing-may be located at the lower part of a suitable cabinet, andthe screen formed as a part of the upper forward wall of the cabinetand. positioned above the printer compartment.

Specifically, the page printer is mounted on rails supported in astructural frame to which i pivotally mounted the lamp housing, in suchmanner that the lamp housing with its condensing lenses is positionablesoas to embrace within the field of projection the last line ofprinting, and also to include eight or ten printed lines. Printing iseffected on a Cellophane strip and the image of the record producedthereon is projected through the optical system onto the screen. TheCellophane web or strip is drawn upwardly through the projection field.The characters on the section of the web in the projection field are .soarranged as to form horizontal lines one above the other, and the imagesof said horizontal lines of characters are projected on the screen. Thehorizontal lines of images on the screen move upwardly across the screensimilar to the movement of the web through the projection field.

The lamp housing together with the condensing lenses is swingableupwardly about its pivotal articulation with the structural frame topermit ready access to the pa e printer. The frame is movable on railsso that the entire structure including the printer and lamp housing maybe rolled outwardly to permit withdrawal and thus' A feature of theinvention resides in providing a disc platen movable with the typecarriage wherein printingis effected on the periphery of I the disc andthe number of hidden printed characters is reduced to a minimum.

The foregoing and other objects and features of the invention willappear "from the following detailed description taken in conjunction wittheaccompanying drawing in which,

Fig. 1 is a cross-sectional view of the printerprojector according tothe present invention;

Fig. 2 is an enlarged side view and partial section of the printermechanism and associated lamp housing and part of the opticalarrangement; r

Fig. 3 is a plan view of the-printer-projector apparatus; g

Fig. 4 is an enlarged cross-sectional view of the printer platen andplaten frame;

Fig. 5 is an enlarged side view of a type bar head; l

Fig. 6 is a view taken substantially on line 66 of Fi 4;

Fig. 7 is a top view of' the part of the printer mechanism shown inFigs. 4 and 6;

Fig. 8 is a perspective view of the shift control mechanism for theprojection field; and

Fig. 9 is an enlarged cross-sectional view of the connection between theplaten frame and the shift control mechanism for the projection field.

Having reference to the drawings in which like reference charactersindicate similar parts throughout the several views, the combinationpage printing and projectingapparatus according to the present inventionis housed in a cabinet,

- provide a track for the frame l5 which supports the page printingapparatus, indicated generally by the numeral It, the lamp housing- I1,and the optical arrangement represented generally by condensing lensesl8, small mirror is and objective'lens 2|. Wheels 22 are journaled tothe bottomside members of the frame I! and cooperate in rolling relationwith rails I, which are provided with indentations 23 into which thewheels 22 are admitted when the frame it, in assuming its fully insertedposition in the cabinet ll, rests upon spacing bosses 25 In the fullyinserted to a crossbar 48 (Fig. ,1) of-frame 26.

p 3 position, the frame I is anchored by'means of bolts to the base ofthe cabinet I I. With this arrangement, the frame is easily insertablein the cabinet. II by means of rollers 22, and moreover is adapted, whenthe properposition has been assumed, to rest upon bosses '25 and then tobe anchored to the cabinet II by bolts.

At each side offrame I5 and disposed at the rear thereof are pivotsupports 24 for a U-shaped frame 26 which carries the lamp housin I1 andcondenser lenses I8. A bar (Fig. 2) is; pivoted to frame 26 and thelower end. of said bar is provided with a hook portion (not shown) bywhich, when the frame 26 i swung upwardly about pivots 24 to facilitateremoval of the printer for servicing, the bar is held in its upwardposition by the engagement of said hooked porcilitate the properpositionment of the image on.

net I I is provided with a series of studs or buttons I2 properly spacedaround the edge of the opening to be covered by screen I3. The screen I3is then fastened to the cabinet II by means of a lacing (not shown)whichpasses alternately tion with a spacer stud-4i! (Fig. 3) in a well-I known manner, the bar. 29 thus serving as a brace or. support. Thelamp housing ,II com prises an outer casing 21 (Fig. 1) which is'securedto a plate 28 fastened to a crossbar 29 of the frame 26. Containedwithin the lamp housing I1 and suitably spaced from the outer igasing 21thereof is a baflle plat 3| which rests upon the bottom of the housingI! and extends upwardly to a point close to the top, as illustrated inFig. l. The bottom of the housing I1 is provided, between the outercasing 21 and the baffle plate 3|, with apertures 32. This constructionpermits the flow of convection-currents between the outer casing 21 andthe ballle plate 3| for cooling purposes. Housing I1 is provided with acover 33 having a grilled section 34 covered by a meshing if desired;Depending from the cover 33 and spaced therefrom is a bafile plate 36(Fig. 1) of substantially the same area as the grilled "opening 34. Lamp31 is adjustably clamped to a bracket 39, which in turn is adjustablysupported by the floor of the housin I1. A reflector 4| is springclamped by a carrier.42 which is adjustably supported, through theinstrumentality of a rod 43 and the enlarged mounting holes for plates45, by the outer casing 21 of the lamp housing I1.

In the embodiment of the invention shown in the drawings, a condensinglens system I6, comprising two plano-convex lenses and one convexoconvexlens, is provided. these lenses being suitthrough the eyelets and aroundthe studs 12, and in this manner the screen is drawn tightly and evenlyacross the opening provided therefor. A corner strip'15 is providedaround the edge of the screen I3 to protect the lacing connectionbetween-the screen and the cabinet.

Having reference .to Fig. 1, a page printer of the type shown in U.S.-Patent 1,904,164 is mount-e ed in the frame I5. The printer,indicated generally as I6, has been modified in certain respects toadapt it for use with the projector of the present invention. The pageprinter comprises the side frames 18 and '19 (Fig. 2)'.to which ispivoted at 8| a platen frame, indicated generally as 82. The usualcylindrical form of platen has been dispensed with in the present embodiment of the invention and has been substituted by the disc form ofplaten I73 shown in Figs. 4, s, and '1, and which will be hereinafterdescribed.

To provide a running account of the message printed on the pagematerial, a delivery mechanism is provided which comprises a means forpermitting the record, material to escape from the supply roll, suitableguides, and a web pulling means whereby the page material is advancedappropriately separated by spacing posts (not shown). Plate 4'1 issecured along its top edge Plates 28, 46, and 41 are suitablyaper'tured'to provide a field of projection of sucharea as to presentupon the screen I3- a predetermined number of line of printing producedon therecord strip.

or web 49 of transparent material.

As previously mentioned, the optical system ofthe present inventionincludes a mirror I9 and an objective lens 2i. includes a mirror 5|supported in the uppe part of the cabinet I I. and through-this systemthe image is projected upon the screen I3. The mirror I9 s adiustablypivoted on a pair of standards 52 by means .of which its angularposition may be determined. Moreover, standards 52 a e adl'ustablymounted on brackets 53 secured to frame IS. The objective lens 2| isadapted 'to be adjustably clamped by a Clamping band 54 which issupported on a U-shaped bracket 56, which in turn is secured to acrossbar 51 on frame I5. Thus, the adjustable mountings provided for themirror I9 and the objective lens 2| fa- The optical system a sothroughth printing zone. Thepage aterial 49 in being delivered from the roll 83is directed over a slack bar 84 which is pivoted at 35 and I is normallybiased clockwise by'a spring 86 to -maintainthe page material orCellophane web taut between the roll 83 and a flanged cylindri cal guide87 carried on a shaft 88 journaled inplates 89 depending from sideframes I8 and E9.

The web 49 is then directed over a roller 9I to which is fixed a ratchetwheel 92, the ratchet Wheel and roller being carried on a shaft 93journaled in the plates 99 secured to side frames 18 and I9. Cooperatingwith the roller 9| is a pressure roller 94 which is carried on a standard 96 secured to a rock shaft 91. Pressure roller 94' is drawn intopressing relation with roller 9| by means of a spring 98. Secured torock shaft 91 and located in juxtaposition to plate 89 is a pressureroller release lever 99. Cooperating with 1 lever 99 is a shoulder IN onplate89 arranged so that when lever 99 is actuated counterclockwise asviewed in Fig. 2) against the action of spring 96 it'wiil latch-upbehind or on the left-hand side of the shoulder IllI, thereby releasingthe pressure roller 94 from engagementwith pressure .roller 9| andmaintaining this condition until lever 99 is again released from theshoulder IOI to permit spring 98 to bring roller 94 again into pressingrelation with roller'9l. Associated with the ratchet wheel 92 is a pawlmember I62 (Fig. 1) which is pivoted to a bell crank lever I93 carriedon a pivot shaft I04. The depending arm of bell crank I93 is pivoted toone end of a push rod I06. the other end of which is shouldered tocooperate with a function bail I08 in the manner shown in theafore-mentioned Patent 1,904,164.

Thus, in response to a predetermined selection a function lever, similarto function lever' I01 shown in 2, is selected to raise the free end ofpush bar I06 upwardly into the path of the function bail blade I08.Then, when the push rod I06 is actuated leftwardly by'the function bailI08, clockwise rotation is imparted to bell crank lever I03 to impart,in turn, downward movement to pawl I02. In this manner, the ratchetwheel 92 is rotated clockwise one step, which, through the cooperationof pressure rollers 9| and 94, acts in cooperation with a web pulling;device to deliver a predetermined amount of record material 49 from thesupply roll 83 to the printing zone and the projection area.

The record material 49 is brought to the printing position by means of apulling or drawing mechanism now to be described. The record material 49as. it leaves roller 9| is directed around guide rods I09, III, and H2.These guide rods may take the form of fixed rods, carrying guide rollersthereon to eliminate friction. From the guide rod II2, the recordmaterial 49 is directed vertically through the printing zone andprojection field to a guide rod II3 carried by a U-shaped shifting framemember II4 (Figs. 1, 2, 3, and 8) pivotally carried on pivots H5 and H6(Fig. 3) suitably journaled in the frame'I5. The page material 49 isthen directed around a guide rod II1 carried in supports II8 (Fig. 2)depending from bars II9 secured to angle iron crossbars I.2I and I22 offrame I5. From thence, the page material 49 is I48, respectively,positioned between side frames 18 and 19. Cooperating with code bars Iare a plurality of pull bars I41 having individual springs I48. Pullbars I41 are operatively connected by rack andv pinion connections to acorresponding plurality of type bars I49 pivoted on a shaft I5I.

Type carriage I42 is also provided with a spacing rack I52 whichcooperates with a spacing mechanism (not 'shown) similar to thatillustrated in Patent 1,904,164. to control the movement of typecarriage I42 to form character spaces, tending in this movement to windup a carriage return spring. mechanism, indicated generally in Fig. 3 asI50, the strap I60 of which is secured to stud I10 fastened to typecarriage I42. Upon receipt of the carriage return signal, a functionlever (similar to lever I01) is selected and the carriage returnmechanism actuated in the manner described in the afore-mentioned Patent1,904,164. Carriage return mechanism I50 is thereupon permitted, due tothe energy stored therein, to return the type carriage I42 to its normalor beginning-of-line position.

A pull bar bail I53 is mounted in the type carriage I42 and is providedwith a roller I54 carried on the bottom side thereof on a-stud I55.

' Roller I54,operates'between a pair of blades I56 directed around aspindle I23 fixed to a shaft I24 journaled in standards I26 supported onsaid bars 9.

Shaft I24 is interconnected through a friction clutch I21 (Fig. 3) to apulley I28. Continuous counterclockwise rotation (as viewed in Fig. 2)

is imparted to pulley I28 through the instrumentality of a belt I29connected to a pulley meshes with a pinion gear I34'fixed to shaft I35Motor I36, therefore,

of a motor I36 (Fig. 1).

and I51 of a main printing bail I58 so that bail I53 can be reciprocatedby bail I58 in any character spacing position of the type carriage I42.Fastened to the printing bail I58 is one end of a printing spring I59,the other end of which is connected to a printing blow adjustment meansas shown in Patent 1,904,164. Bail I58 ismounted on a shaft I61 on whichis also carried a printing bail actuator I62 which cooperates with aprint- .ing cam I63. Actuator I62 carries at the end of its upper arm astud I64 which has abutting relation only with printing bail I58 and isnot permanently connected thereto, which is to permit spring printing.Printing bail I58 is also provided with a pair of arms I66 which carry athrough gears I34 and I33, shaft I32. pulley I'3I,

and belt I29 imparts continuous rotation to'pulley I28 which through thefriction clutch I21 impartsa constant torque through shaft I24 to thespindle I23. With this arrangement the page material 49 is maintained ina' taut condition between the spindle' I23and the roller 9I. Thus,'

when the ratchet 92 is rotated one step a predetermined amount of thepage material 48 is delivered from the supply roller 83, which mate- Iselector magnet I31 of a sword and T-type.

selector (not here shown, but illustrated and described in said patent)a series of selector vanes function lever bail I69. Also carried onshaft I6I is a function bail comprising arms I and I61. Arm I65 isprovided with a follower roller which cooperates with a function bailcam I68, and

arm 161 supportson its end the function bail blade I08.

Associated with the selector vanes I38 are a plurality of functionlevers I01 mounted on pivot rod HI and provided with individual springsI12 which tend to rotate the function levers clockwise into registrywith the selector vanes I38. The function levers I01 are normally heldout of engagement with the selector vanes I38 by means of the rod I69 ofthe function lever bail.

I13 being located coincident with the printing point or zone determinedby the path of operation of the type bar I49.

The platen frame 82 is adapted to be rocked from the "letters or unshiftposition to the "figures or shift position in the manner fully set forthin the aforementioned Patent 1,904,164. Briefly, the side frame of theplaten frame 82 (as shown in Fig. 2) is provided with 9; lug I11 1 245mounted on arms 246 and v of bracket 248 fixed to the crossbar I2I(Figs. 2

and 8).

which operates between two adjustable stops I18 and I19. Adjacent to lugI11 there is pivoted to the side frame of the platen frame 82 on pivot1I8I, the upper end of a link I82, the lower end of which is pivoted tothe horizontal arm of a bell crank 1ever.I83 pivotally mounted at 184.To the lower end of the depending arm of bell crank I83 is pivoted pushbar I85, the free end of which overlies a leftwardly directed arm of thefunction lever I01. Push bar I85 is also provided This condi- Acorrespondingly similar construction is pro- ;vidcd for the figures orshift mechanism. That is, a shift functionlever similar to lever I01 is.DlOVidBd which when selected is caused to rotate clockwise to bring itsrearwardly extending arm into operation to raise a push bar, similar tobar respectively (Figs. 2 and 8). Members 259 and '26! are each providedat the upper end thereof with an open-ended slot 260 which fits over theshank of a headed stud 261'and 266, respectively. With this arrangement,the members 259-and 26I may be easily disconnected from studs 265 and266 so as to render the printer readily detachable from the frame I5.Supported by the depending arms of the levers 259 and 26I is the pre-I85, into the path of the function bail blade I08 1 i which. when it ispermitted to operate leftwardly as viewed in Fig. 2) will cause a bellcrank, similar to bell crank I83, to pull down a link similar 3 to linkI82 to rock the platen frame 82'counterl clockwise to bring its stop I11against the lower 1 stop screw I19. The platen frame 82 is main- 1tained in its shift or unshift position by a spring actuated, detentmember. I81 acting on a detent 3 roller I88.

An arrangement is provided, according to the 1 present invention, foraccurately controlling and accelerating the shifting movement of thepor- 1 tion of the record material which is in the field of projection,in response to corresponding moveframe member II4, which is pivotallysupported at I15 and H6 in the framel5, carries a guide 1 rod II3 forthe record strip 49 which cooperates with guide rod II2 to guide therecord material 1 through the field of projection. Frame member H4 isoperable between adjustable stops 244 and Mounted on bracket 248 areelements compris- 1 ing an overcentering device which cooperate with theshift frame 82 to effectuate the'control of the record strip in theprojection field. The overcen- 1 tering device comprises a lever arm2.49 pivoted at 25I to bracket 248, and is articulated to the member H4at 252. Lever 249 terminates in a forked end 258 in which a stud 254. isslidably op- 1 erable'. Stud 254 is mounted on the end of a lever arm255 pivoted at 256 to bracket 248. A spring 251 is extended between stud254 and a spring post 258 carried on bracket 248. Spring post 258 andpivots 25I and 256 arearranged on a com-. mon center line substantiallyintermediate the stops 244 and 245 so that bar II4, after passing overcenter above or below said line, will be urged byspring 251 againststops 244 or 245, respectively. 4

Member H4 is connected to the platenframe I I4 is illustrated as movablewith platen frame 82. To assure a definite extent of movement of frame4, the stops 244 and 245 are provided. The platen frame 82 is shiftablebetween stops I18 and I19 by the spring action of detent I81 which is inthe nature of an overcentering means because, as link I82 acts to rockthe platen frame 82 between the two shift positions, they camming actionof detent- I81 operates to assist and hasten the shifting movement. Theaction of the overcentering device mounted on bracket 248 is comparable,and to permit this assisting action, the hole-266 (Fig. 9) in each ofthe levers 259 and 26I is elongated so that the overcentering actiontakes effect immediately u ter independently of the entire movement ofplaten frame 82, and urges frame II4 into proper position against one orthe other of the adjustable stops 244 or 245. In'other words, the platenframe 82 begins the movement of theframe H4, and the overcenteringdevice completes this -movement suddenly upon passing. over center, the

mg device to take the control of the frame H4 from the platen frame 82.

. ment of the platen between the upper and lower 1 case shift positions."Accelerating the web shift minimizes the optical effect upon the image,As previously alluded to, the U-shaped shifting 241, respectively,

82 by means of a pair of lever members 259 and I 26I which are pivotedto frame 82 at 282 and 263.

In Figs. 4, 6, and 7 is illustrated the manner in which the platencarriage I14 is connected to the type carriage I42 so as to be movabletherewith. As previously mentioned, the platen carriage I14 is slidablysupported on rods I15 and I16. Carriage I14 is provided with aneccentric stud engaged by the forked end of a bar I89, the left end ofwhich (as viewed in'Fig. 6) is secured to a member I9I which is securedby screws I92 to the type carriage I42. As viewed in Fig. 7, thecircular platen I19 is rotatably mounted on, the platen carriage I14 bymeans of an eccentric screw means I93. By means of the adjustment I98,the platen I18 is adjustable toward and away from the, record materialto vary the clearance therebetwee'n. Rightward and leftward adjustment,as viewed in Figs. 6 and '1, is also provided for the platen I18,through the instrumentality of the eccentric adjusting means I90.

An important feature of the present invention is the provision of aplaten so positioned as to reduce to a minimum the obstruction of theprojected image by the platen. To achieve this result the platen I13 istilted, with respect to the record material printed upon, sufficientlyto clear the light cone. The peripheral surface of the platen I18, uponwhich printing is effected, is slightly beveled so that in one of theshift positions ofthe platen the'peripheral surface of the platen' wilibe parallel to the record material. In the present embodiment theperipheral sur face of the platen I18is parallel to the record stripwhen the platen frame 82' has been shifted n passing over cenprovidedwith an upper case type face I96 and a lower casetype face I91 (Fig.However, according to the presentinvention the lower case cumulated onthe type face I91 from smudging the record material. Y

As illustrated in Figs. 4, 6, and '7, there is provided a platen rotatorfor automatically changing theprinting point of the platen I 13 inresponse to each carriage return operation. As previously describedgtheplaten I13 spaces with the type carriage I42, and accordingly is spacedstep by type face I 91 is provided with a slope corresponding to theslope of the periphery of the platen I13 when in the lower caseposition, The dimension 201 of the upper case type I96 is arranged to beslightly less than the minimum height 2I0 of the lower case type I91.When printing iseiiected in the lower case .position, the type face I95,being lower than the-type face I91, will not touch the record materialand hence no smudging of the printed record will occur.

When printing is effected inthe upper case position, means is .providedfor preventing the lower case type face I91 froni coming into directcontact with the surface of the record material. To achieve this resulta shield I95 is provided which is adapted to be interposed between thetype face I91 and the platen I13 when printing isbeing ef-' fected inthe upper case position. ,Shield I95 is which, as described in theafore-mentioned Patstep for character spacing and, upon reaching the endof the line, the platen I13 is returned rapidly with the carriage I42 tothe beginning-of-line position. In contact with the platen I13 at apoint opposite to the printing point is a closely wound v coiled spring200'which is connected at itsends to the side frame members of theplaten supporting frame 82, in such a manner that the platen I13 iscaused to rotate as it advances during character spacing. Moreover, uponthe rapid 'ret'urn movement of the platen I13 (under the influence ofthe carriage return spring I50) during the performance of the carriagereturn function, the platen I13 will, owing to the combined sliding androlling relation with the yieldable spring member 200, rotateincommensurately, thus causing the I secured to the ribbon oscillatingmember, I99,

ent 1,904,164, oscillates the inking ribbon into and out of the path ofthe type faces during the printing operation. The ribbonoscillator I99is pivotally articulated to arm ml of a lever 202 which in turn ispivoted at 203 to alever 204 pivoted at 220 to the type carriage I42.Lever 204 is arranged to carry a roller 205 which rides on the bottomside ofa rail 206 mounted on the platen frame 82, as disclosed in theafore-mentioned Patent 1,904,164. Roller 205 is pressed against the rail206 by a spring (not shown), so that when the platen frame 02 is rockedbetween the shift and unshift positions, roller 205 will constantlycontact with said rail 205, and lever 202 will be reciprocatedtherewith.

same printing point of the platen to be presented to the type bars aminimum number of times. In other words, through the instrumentality ofthe platen rotator 200, the platen I13 is controlled i in such manner asto reduce to a minimum the number of times any particular printing pointon the platen is impinged upon, thereby reducing to a minimum the .wearat" any given point and hence prolonging the life of the platen. In lieuof the coiled spring 200, a taut wire or cord can, of I course, be used.

It is understood that the features of the present invention are not tobe limited to the specific forms described herein, but embrace all formsThe depending arm 208 of the lever 202 is op- 1 erably associated withthe, pull bar bail I53 (Fig.

. 2) so that the reciprocative motion of bail I53 will cause theoscillation of the lever 202 about pivot 203, whether the platen frame82 is-in the shift or the unshift position. Thus, when the bail I53 isin its normal position (the leftward position as shown in Fig. 2), thelever 202 will hold the inking ribbon, through the instrumentality ofthe ribbon guide (not shown) located at the upper extremity of memberI99 (Fig. 4) in its downward position to efiect visibility of theprinted character. When the bail I53 moves rightwardly for a printingoperation, the ribbon will be raised to printing position due to thecounterclockwise movement imparted to thelever 202 by the bail I53. Whenthe platen frame 02 is in the position shown in Fig.4, which is thelower case printing position, the shield I95. upon oscillation of lever202 will not be raised sufficiently to be interposed between the typeface I91 and the platen I13. However, when the platen frame 92 is in theupper case printing position with the platen I13 in printing relationwith the upper case type face I96, the'shield I95 will, uponreciprocation, be raised soas to become interposed between the lowercase type face I91 and the record mawhich come within the scope ofequivalency of the appended claims.

What is claimed is:

v 1. In a printing apparatus, paper supporting means, a printing bail, aplurality of type bars, means for supporting said type bars, said meansslidably articulated to said printing bail, means for moving said typebarsupporting means relative to said paper supporting means to formcharacter spaces, a platencooperably related to said type bars, meansfor shifting said platen between two positions indicative of upper andlower case, and means for rendering said platen movable with said typebar supporting means in character spacing movement irrespective of thecase shifting operation of the platen shifting means.

2. In a printing apparatus, a printing bail, a

plurality of type bars, means for supporting said type bars, said meansslidably articulated to said printing bail, means for moving saidsupporting means in character spacing direction, a platen cooperablyrelated to said type bars, means for shifting said-platen between twopositions in-- 3. In a printing apparatus, paper supporting terial, thuspreventing any in]: which has 9.0- .751 means, a Printing-bail, amovable type carriage slidably articulated to said printing bail, meansfor advancing said type carriage relative to said paper supporting meansto form character spaces, a platen cooperably related to said typecarriage, meansvfor'shiftin'g said platen between two positionsindicative of upper and lower case irrespec-' I 12 printing bail, aprinting device having a carriage slidably articulated to said printinghail,

said carriage supporting a plurality of pivoted type bars movable inprinting toward a common locus, means for advancing said type carriagerelative to said paper supporttive of the relative articulativepositionment of Q said bail and said type carriage, andmeans forrendering said platen movable with said type car'- riage in characterspacing movement independently of the case shifting movement of saidplaten shifting means. p

4. In a printing apparatus, paper supporting means, a printing bail, aplurality of type bars,

means for supporting said type bars, said means slidably articulated tosaid printing bail, means for advancing said type carriage relative tosaid paper supporting means to form character spaces, a platencooperably related to said type bars, meansfor shifting s'aid platenbetween two positions indicative of upper and lower case irrespec- 5. Incombination, web supporting means, a

. tive of the relative articulative positionment of 1 said bail and saidtype carriage, and means for rendering said platen movable with said'type bar supporting means in character spacing movement independently ofthe case shifting movement of said platen shifting means.

carriage with said platen carrier whereby character spacing movement isimparted to said platen carrier, means for shifting said platen carrierbetween two positions indicative of upper and lower case irrespective ofthe relative articulative positionment of said bail and said carriage,and means eiIective at the point of articulation between said platencarrier and said type carriage for rendering said platen carrier movablein character spacing movement independently of the case shiftingmovement of said platen shifting means.

WALTER J. ZENNER.

